Invalid path reference articles.title; Associations can only be pointed to directly or via their id property

[kliarist]

I am using spring-graphql along with spring-data-mongo and querydsl and faced with the below issue

org.springframework.data.mapping.MappingException: Invalid path reference articles.title; Associations can only be pointed to directly or via their id property
	at org.springframework.data.mongodb.core.convert.QueryMapper$MetadataBackedField.getPath(QueryMapper.java:1275) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.convert.QueryMapper$MetadataBackedField.<init>(QueryMapper.java:1134) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.convert.QueryMapper$MetadataBackedField.<init>(QueryMapper.java:1111) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.convert.QueryMapper.createPropertyField(QueryMapper.java:365) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.convert.QueryMapper.lambda$mapFieldsToPropertyNames$0(QueryMapper.java:234) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at java.base/java.util.Map.forEach(Map.java:713) ~[na:na]
	at org.springframework.data.mongodb.core.convert.QueryMapper.mapFieldsToPropertyNames(QueryMapper.java:232) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.convert.QueryMapper.getMappedFields(QueryMapper.java:220) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.QueryOperations$QueryContext.getMappedFields(QueryOperations.java:363) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.MongoTemplate.doFind(MongoTemplate.java:2573) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.ExecutableFindOperationSupport$ExecutableFindSupport.doFind(ExecutableFindOperationSupport.java:177) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.core.ExecutableFindOperationSupport$ExecutableFindSupport.all(ExecutableFindOperationSupport.java:135) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.data.mongodb.repository.support.SimpleMongoRepository$FluentQueryByExample.all(SimpleMongoRepository.java:391) ~[spring-data-mongodb-4.1.1.jar:4.1.1]
	at org.springframework.graphql.data.query.QueryByExampleDataFetcher$ManyEntityFetcher.getResult(QueryByExampleDataFetcher.java:751) ~[spring-graphql-1.2.1.jar:1.2.1]

Here is my set up :

@AllArgsConstructor
@NoArgsConstructor
@Getter
@Setter
@Builder
@EqualsAndHashCode
@QueryEntity
@Document(collection = "articles")
public class Article {

    @Id
    private String id;
    private String title;
    private Integer minutesRead;
    @DBRef(lazy = true)
    private User author;
}

@AllArgsConstructor
@NoArgsConstructor
@Getter
@Setter
@EqualsAndHashCode
@Builder
@QueryEntity
@Document(collection = "users")
public class User {

    @Id
    private String id;

    private String name;
    private Integer age;
    private Date createdAt;
    private String nationality;
    private List<String> friendsIds;
    @DBRef(lazy = true)
    private List<Article> articles;
}

@GraphQlRepository
public interface UserRepository extends MongoRepository<User, String>, QuerydslPredicateExecutor<User> {
}

here is my graphql schema:

type Query {
    users: [User]
     ...
}

👍 So while the following graphql seems to work fine:

query {
  users {
    id
    age
    name
    articles {
      id
    }
  }
}	

❌ adding extra properties on the nested articles object does not:

query {
  users {
    id
    age
    name
    articles {
      id
      title
    }
  }
}	

throwing org.springframework.data.mapping.MappingException: Invalid path reference articles.title; Associations can only be pointed to directly or via their id property.

Can you please shed some light as to what is the problem here ?

Also, I have noticed that when using MongoRepository along with QuerydslPredicateExecutor then QueryByExampleDataFetcher takes precedence over QuerydslDataFetcher. Is this expected behaviour?

[bclozel]

Inline code snippets don't really help here. Can you share the full sample application that we can use to replicate the problem?

[rstoyanchev]

Also, I have noticed that when using MongoRepository along with QuerydslPredicateExecutor then QueryByExampleDataFetcher takes precedence over QuerydslDataFetcher. Is this expected behaviour?

We generally don't expect both, and if both are implemented the order is not defined.

[kliarist]

Inline code snippets don't really help here. Can you share the full sample application that we can use to replicate the problem?

Thanks for the quick response. Sure. here is a sample project to reproduce it.

[kliarist]

Also, I have noticed that when using MongoRepository along with QuerydslPredicateExecutor then QueryByExampleDataFetcher takes precedence over QuerydslDataFetcher. Is this expected behaviour?

We generally don't expect both, and if both are implemented the order is not defined.

Thanks. I see.. I need the QuerydslPredicateExecutor present tho, as I will need the predicate builder functionality in the future.

[mp911de]

This is a Spring Data problem when attempting to project properties from an association. I filed spring-projects/spring-data-mongodb#4453 to address the issue.

[kliarist]

@mp911de I see.. thanks